1. Field of the Invention
The present invention relates to an automated multiple-needle sewing machine which is capable of sewing a pre-formed material, such as a central cover section of a trim cover assembly for an automotive seat.
2. Description of Prior Art
A typical type of trim cover assembly for an automotive seat is formed to have a central cover section and a pair of lateral bolster cover sections for covering the corresponding portions of a foam cushion member. Conventionally, the central cover section in this sort of trim cover assembly is of a three-layer lamination type comprising a top cover member, a foam wadding of a urethane foam slab material and a wadding cover in this order. Those three layers have been cut into a predetermined proper shape corresponding to the flat central seating area of the seat and then been sewn together by means of a multiple-needle sewing machine, such that a plurality of decorative rectilinear seams are left thereupon.
Normally, the multiple-needle sewing machine has a plurality of sewing needles disposed transversely thereof or in the width-wise direction thereof, and thus, the rows of those needles lie in a direction orthogonal to the direction wherein the foregoing trim cover assembly lamination material is fed toward the needles for sewing, as known from the U.S. patent application Nos. 838,367 now U.S. Pat. No. 5,193,474 and 838,374 assigned to the assignee of the present invention.
However, in operating this sort of conventional multiple-needle sewing machine, it has been found defective that an operator has to keep stretching the lamination material and feeding it to the needles, with his or her hands, until the sewing is completed, in an attempt to avoid any slackened or crease portion in the material as well as a curvature in sewing.
A solution to this problem may be conceived by providing a securing plate in the sewing machine, which is designed to secure the trim cover assembly material thereon in an uniformly stretched state and slidable forwardly and backwardly with respect to the sewing machine body having the plural needles. But, this gives the operator a hard time, because he or she needs to move from one end to another end of the machine to carry again the securing plate to a feeding position for securing again a new other cover base material thereon for next sewing stage.